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From: Thomas Kellerer <spam_eater@gmx.net>
To: pgsql-performance@lists.postgresql.org
Subject: Re: Query is slow when run for first time; subsequent execution is fast
Date: Tue, 16 Jan 2018 13:20:39 +0100
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Nandakumar M schrieb am 12.01.2018 um 09:03:
> Even if I close a connection and open a new one and execute the same
> query, the planning time is considerably less than the first time.
> Only when I restart the Postgres server then I face high planning
> time again.

Yes, because the data is cached by Postgres ("shared_buffers") and the filesystem.

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